Gillard on attack over superannuation

Prime Minister Julia Gillard is pressuring the coalition over its superannuation plans, even though Labor has declined to guarantee it won't change the treatment of retirement savings.

In parliamentary question time, the coalition challenged the prime minister to guarantee - as Opposition Leader Tony Abbott had - "no unexpected adverse changes to superannuation".

Ms Gillard said the coalition pledge was a "fudge", given Mr Abbott had already said he would scrap the mining tax - which funds a tax break on superannuation for 3.6 million people earning under $36,000 a year.

"When you have hacked into 3.6 million Australians I'm not surprised you've then said no further changes - the evil work has already been announced," she told parliament on Thursday.

Superannuation Minister Bill Shorten declined to rule in or out any changes to tax concessions for retirement savings in the coming budget.

"Labor has the track record of being the people that when hard decisions have to be made, we have improved the system for all," he told reporters.

"I believe our system is better than the coalition's alternative."

Ms Gillard told parliament on Wednesday the government would "never remove tax-free superannuation payments for the over-60s", including lump sums and pensions.

However, it's feared the May budget measures may include charging a higher marginal rate when super is being accumulated by the wealthiest one per cent of Australians.

Mr Abbott argued Labor had broken its 2007 pledge that it would not interfere with superannuation.

"If we are going to do the right thing by the people of Australia, particularly the small business people of Australia, we've got to get taxes down, not up," he told reporters in Queanbeyan, where he attended a small business roundtable.

The opposition leader's own draft tax plans came under fire on Thursday, following the leak of a draft discussion paper titled Developing Northern Australia - a 2030 Vision.

The paper says there's "tremendous potential" in northern Queensland, the NT and Western Australia and it proposes tax and other incentives to develop urban zones around Darwin, Cairns-Townsville and Karratha.

Another idea is to shift large numbers of public servants from metropolitan areas to northern Australia.

However, Mr Abbott dismissed the paper as "not even a finalised discussion paper".

"It's certainly not policy," he said.

But there was "nothing wrong" with a system of "careful, fiscally responsible incentives".

Trade Minister Craig Emerson said the ideas were "very, very expensive, ill-thought out" and had been leaked to the media by disgruntled people in the Liberal Party.

Still, Nationals Senate leader Barnaby Joyce said some of the paper's ideas should be pursued.

Meanwhile, Ms Gillard's pledge not to introduce a levy to pay for a major budget promise - the National Disability Insurance Scheme - has been questioned by a Labor backbencher.

Ed Husic, who represents the western Sydney seat of Chifley where Labor is facing a major battle in this year's election, said the potential cost of the historic reform was $15 billion annually.

"People will be open to considering that the NDIS gets funded in part by the Medicare levy," he said.

The government is trying find budget savings to support the scheme.

This material is subject to copyright and any unauthorised use, copying or mirroring is prohibited.